1. Field of Invention
The present invention relates to an igniter assembly for use in a gas generator and to an assembling method therefor.
2. Description of Related Art
Because of an advantage in cost thereof, a structure in which an igniter main body is integrated with an igniter collar by a resin is presently widely used in igniter assemblies. A resin or the like is used for integration and the assembling is performed by an injection molding method.
JP-A No. 11-321541 (U.S. Pat. No. 6,073,963) discloses an igniter assembly for use in a gas generator for an air bag. When an injection molding method is employed to assemble the igniter assembly, a molding die is used, but as shown in FIG. 1 and FIG. 2, the strength of the inward flange portion (inner section 80) of the collar has to be increased by increasing the thickness thereof so that the igniter main body does not slip through a hole formed in the collar (insertion member 40) when some force is applied to the igniter main body after the resin has been melted by the heat of an ignition agent during actuation after incorporation in a gas generator or the like.
However, if the thickness of the inward flange portion is increased, the space for inserting an injection mold into the collar is decreased and, for example, a gap is difficult to form between the collar and the injection molding mold located below the collar and the resin can hardly flow smoothly into the mold. In particular, in the case where only one resin injection port is provided (for example, only above the collar) to simplify the injection apparatus, the gap formed between the collar and mold is decreased, thereby impeding the flow of resin into the zone below the collar.